There are various types of digital display systems known in the art. In one type, individual light emitting elements, commonly called light emitting diodes (LED's) or the like, are arranged in a pattern in clocks and display boards. The individual LED's are turned on and off to display a given message or to show the time. In another type, a chemical material is sandwiched between two electrode plates where at least one of the plates has been etched with segments for displaying alpha and/or numeric symbols. The segments are activated by the selective application of an electric field to the selected segments.
Another type of display unit, called a liquid crystal display (LCD) is a thin flat display device made up of any number of color or monochrome pixels arrayed in front of a light source or light reflector. Each pixel of an LCD consists of a layer of perpendicular molecules aligned between two transparent electrodes, and two polarizing filters, the axes of polarity of which are perpendicular to each other. With no liquid crystal between the polarizing filters, light passing through one filter would be blocked by the electrodes. The surfaces of the electrodes that are in contact with the liquid crystal material are treated so as to align the liquid crystal molecules in a particular direction. Before applying an electric field, the orientation of the liquid crystal molecules is determined by the alignment at the surfaces. The surface alignment directions at the two electrodes are perpendicular and so the molecules arrange themselves in a helical structure, or twist. Because the liquid crystal is birefringent, light passing through one polarizing filter is rotated by the liquid helix as it passes through the liquid crystal layer, allowing it to pass through the second polarizing filter.
When a voltage is applied across the electrodes, a torque acts to align the liquid molecules parallel to the electric field, distorting the helical structure. This reduces the rotation of the polarization of the incident light and the device appears gray. If the applied voltage is large enough, the liquid crystal molecules are completely untwisted and the polarization of the incident light is not rotated at all as it passes through the liquid crystal layer. The incident light will then be polarized perpendicular to the second filter, and thus be completely blocked and the pixel appears black.
There are other types of display systems called photochromatic display systems and cataphoresis display systems. In some of these systems, as well as LCD's, backlighting has been added in order to aid the individual in reading the display when there is little artificial or natural light available.
Many types of electronic products utilize these types of displays for digital clock systems in such diverse applications as table and wall clocks, automobile clocks, microwaves, washing machines, VCRs and the like. Of these, the table and wall style mounted clocks are one of the more common in use. In the case of hotels, motels and other places the public frequents, these clocks generally have only one side, or face, for displaying the time. Thus, in the case of a hotel or motel where there are multiple beds, only one person can have the clock face facing them. If the other person wakes up in the night and desires to determine the time, they have to search for the clock and then turn it to face them in order to read the time. In addition, during the non-sleeping hours, the face of the clock is not always visible from persons located in various parts of the room, thereby requiring the user to reposition them selves in order to get a clear line of site at the clock face in order to read the time displayed on the clock.
In the case where there are multi-faced clocks, particularly in public places such as airports, train stations and the like, the multi-faced clocks are generally designed in one of two fashions. In one form, they are designed to look like the older style analog clocks that have a round face and two arms, one of which indicates the hour and the other the minutes. In this structure, the visual appearance of the multiple-faced clock has a symmetrical and pleasing appearance. In the other type of structure, where a digital display is utilized, the clocks are designed with clock faces that are parallel to each other such that only one display is viewable at a given time by a single viewer. The reason for this is that digital faced clocks are all right justified, meaning that the time shown is always shifted to the right hand side of the display. If multiple faces of a digital clock were visible simultaneously by a user, they would appear to be non-symmetrical and esthetically unappealing. As depicted in the prior art of FIG. 2, a right hand side of a clock face would depict the time right justified with a gap towards the front of the clock while the clock face on the left hand side of the clock would also depict the time as being right justified which would therefore leave a gap towards the rear side of the clock. Thus, digital clocks suffer the drawbacks of either having only one face presented to a user or a multi-faced digital clock that appears unsymmetrical and esthetically unappealing.
Therefore, it is an object of this invention to provide a digital multi-faced faced clock that provides for the display of time that appears centered relative to the time display panel.
It is a further object of this invention to provide a multi-faced digital clock wherein all of the clock faces are symmetrical with respect to each other clock face.
Other objects, features and advantages of the invention will be apparent from the following description taken in conjunction with the drawings.